I've visited Mai Thai more times than I can count throughout the time I lived in Wheaton.
The food was always delicious, the service excellent, and the portions just right. It's a small family owned restaurant with a few tables and take out available. You definitely don't go there for the decor (it is a very small and basic dining area), but for the food, and oh the food is good!
I never had anything from the menu that I didn't like. Some favorites included the floating market soup (if you like seafood), shrimp soup, Thai fried rice, garlic madness, and the classic pad thai. Everything is cooked to order and super fresh. The spices are just right and you can specify if you want mild, medium, or spicy. Be warned, the spicy is SPICY. I always ask for the spicy, but if it's your first time at Mai Thai, I would try medium and if it's your first time having Thai food, go for mild.
I love this restaurant and highly recommend it to anyone. Expect to pay around $10 for a meal, a couple of dollars for drinks.